"But a powerful new type of computer that is about to be commercially deployed by a major American military contractor is taking computing into the strange, subatomic realm of quantum mechanics. In that infinitesimal neighborhood, common sense logic no longer seems to apply. A one can be a one, or it can be a one and a zero and everything in between - all at the same time. [...] Now, Lockheed Martin - which bought an early version of such a computer from the Canadian company D-Wave Systems two years ago - is confident enough in the technology to upgrade it to commercial scale, becoming the first company to use quantum computing as part of its business." I always get a bit skeptical whenever I hear the words 'quantum computing', but according to NewScientist, this is pretty legit.

It's like the old child's game where you state the largest number, and finally someone says infinity, and then someone says infinity+1 - no dude, infinity is defined as the largest number, and quanta as the smallest discrete unit - as the infinitesimally small.

Well, Infinity + 1 is larger.
Infinity isn't "The largest number" because there is no "largest." (That implies that it stops and there is nothing larger).

Infinity + 1 is larger than Infinity in the same sense as "The set of real numbers" is larger than "the set of whole numbers." Both are infinite in size, but Set of Real Numbers contains elements that aren't in the Set of Whole Numbers.